Just for Laughs was founded in 1983 by Gilbert Rozon as a two-day French language event. In 1985, Andy Nulman joined the festival's staff and introduced English language events as well; under Nulman's stewardship, the festival increased to a full month, with French-speaking performers during the first half, and English speakers in the second half. International and non-verbal acts (acrobats, pantomimes, etc.) are scattered throughout the program.

In 1999, Nulman left the festival's full-time employ; however, he directed its major Gala Shows at the Saint-Denis Theatre every July, and remained on the board of directors of the festival's parent company. After an 11-year absence, Nulman returned to Just for Laughs in July 2010 as president of Festivals and Television.[2]

Each day, performers, "New Vaudevillians" and other acts both vocal and visual perform throughout the city, particularly in the "Latin Quarter"—an area known for its theatres, cafés and boutique shopping. In the evenings, the nightclubs and live venue theatres offer special programs supporting the performers.

Although Just for Laughs attracts spectators from around the world, many of those in the audience are talent scouts, booking agents, producers and managers from the entertainment industry. Performing at the festival is one of the biggest opportunities for undiscovered talent to showcase their act in front of industry professionals.

The Just for Laughs festival also has the Comedia comedy film festival component, which started in 1996. It gives awards for feature and short films. 2005, Comedia screened 125 short films from around the world as well as several feature-length films.

In February 1994, the festival sponsored a splinter project in Hollywood, Florida. That coastal area is a favourite winter destination for Quebecers who head south to vacation in the warmer weather. The event, Juste Pour Rire—En Vacances (Just For Laughs—On Vacation), was held in the Young Circle Park, an outdoor venue with an urban park setting.

In July 2007, Just For Laughs celebrated its 25th edition, launching a festival in Toronto, Ontario.

On October 18, 2017, festival president and founder Gilbert Rozon resigned from his position following allegations of sexual misconduct.[6] Rozon later announced that he would sell the festival. As per a partnership with the conglomerate, Quebecor was given right of first refusal to counter competing offers. The company, however, declined. On March 21, 2018, it was announced that the festival would be acquired by a partnership between U.S.-based talent agency ICM Partners and Canadian comedian Howie Mandel. In their announcement of the purchase, it was stated that Just for Laughs would remain based in Montreal (with Mandel considering the event to be a key component of local culture), and that there would be no changes in its management or operations. It was also stated that the partnership was seeking other local partners. Quebecor subsequently announced that it would become a "founding partner" of Le Grand Montréal Comédie Fest—a competing event that was being established by a group of Quebecois comedians as a competitor in the wake of the Rozon scandal.[7][8]

In May 2018, La Presse reported that the partnership planned to sell a 51% stake in Just for Laughs to Bell Canada and Evenko, so that the event would remain majority-owned by Canadian interests (and thus remain eligible for government tax credits).[9] On June 7, 2018, Just for Laughs confirmed that Bell Media and Groupe CH had acquired stakes in the festival.[10]

Tapings from festival performances have been featured in Just for Laughs-branded television programs and specials, which have aired on channels such as CBC Television, The Comedy Network (including the original Just for Laughs series, as well as a new series that premiered in 2012, Just for Laughs: All Access), and TVA.

The festival has also lent its name to a hidden camera comedy series, Just for Laughs: Gags, which has also been aired by various Canadian channels, and has been sold internationally.